Combinatorics and Graph Theory — One Question at a Time
Practise 200 Combinatorics and Graph Theory multiple-choice questions covering counting methods, permutations, combinations, graphs, trees, shortest paths and asymptotic notation. Work through one question at a time, check the correct answer with an explanation, and select Next Question to continue. This is self-paced practice without automatic scoring.
Before you practise: Read Combinatorics and Graph Theory study material and examples. You can also browse all 1,576 interactive MCQs.
Question 1. How many ways can 3 distinct books be arranged on one shelf?
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Correct answer: A. 6
There are 3! permutations of 3 distinct objects.
Question 2. A student chooses one of 3 shirts and one of 4 pairs of trousers. How many outfits are possible?
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Correct answer: B. 12
By the product rule: 3×4=12.
Question 3. A menu offers 3 desserts or 5 drinks as a single choice (disjoint options). How many choices?
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Correct answer: A. 8
By the addition rule: 3+5=8.
Question 4. How many ways can 4 distinct books be arranged on one shelf?
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Correct answer: D. 24
There are 4! permutations of 4 distinct objects.
Question 5. A student chooses one of 4 shirts and one of 5 pairs of trousers. How many outfits are possible?
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Correct answer: A. 20
By the product rule: 4×5=20.
Question 6. A menu offers 4 desserts or 6 drinks as a single choice (disjoint options). How many choices?
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Correct answer: D. 10
By the addition rule: 4+6=10.
Question 7. How many ways can 5 distinct books be arranged on one shelf?
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Correct answer: C. 120
There are 5! permutations of 5 distinct objects.
Question 8. A student chooses one of 5 shirts and one of 6 pairs of trousers. How many outfits are possible?
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Correct answer: D. 30
By the product rule: 5×6=30.
Question 9. A menu offers 5 desserts or 7 drinks as a single choice (disjoint options). How many choices?
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Correct answer: C. 12
By the addition rule: 5+7=12.
Question 10. How many ways can 6 distinct books be arranged on one shelf?
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Correct answer: B. 720
There are 6! permutations of 6 distinct objects.
Question 11. A student chooses one of 6 shirts and one of 7 pairs of trousers. How many outfits are possible?
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Correct answer: C. 42
By the product rule: 6×7=42.
Question 12. A menu offers 6 desserts or 8 drinks as a single choice (disjoint options). How many choices?
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Correct answer: B. 14
By the addition rule: 6+8=14.
Question 13. How many ways can 7 distinct books be arranged on one shelf?
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Correct answer: A. 5040
There are 7! permutations of 7 distinct objects.
Question 14. A student chooses one of 7 shirts and one of 8 pairs of trousers. How many outfits are possible?
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Correct answer: B. 56
By the product rule: 7×8=56.
Question 15. A menu offers 7 desserts or 9 drinks as a single choice (disjoint options). How many choices?
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Correct answer: A. 16
By the addition rule: 7+9=16.
Question 16. How many ways can 8 distinct books be arranged on one shelf?
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Correct answer: D. 40320
There are 8! permutations of 8 distinct objects.
Question 17. A student chooses one of 8 shirts and one of 9 pairs of trousers. How many outfits are possible?
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Correct answer: A. 72
By the product rule: 8×9=72.
Question 18. A menu offers 8 desserts or 10 drinks as a single choice (disjoint options). How many choices?
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Correct answer: D. 18
By the addition rule: 8+10=18.
Question 19. How many ways can 9 distinct books be arranged on one shelf?
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Correct answer: C. 362880
There are 9! permutations of 9 distinct objects.
Question 20. A student chooses one of 9 shirts and one of 10 pairs of trousers. How many outfits are possible?
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Correct answer: D. 90
By the product rule: 9×10=90.
Question 21. A menu offers 9 desserts or 11 drinks as a single choice (disjoint options). How many choices?
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Correct answer: C. 20
By the addition rule: 9+11=20.
Question 22. How many ways can 10 distinct books be arranged on one shelf?
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Correct answer: B. 3628800
There are 10! permutations of 10 distinct objects.
Question 23. A student chooses one of 10 shirts and one of 11 pairs of trousers. How many outfits are possible?
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Correct answer: C. 110
By the product rule: 10×11=110.
Question 24. A menu offers 10 desserts or 12 drinks as a single choice (disjoint options). How many choices?
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Correct answer: B. 22
By the addition rule: 10+12=22.
Question 25. How many ordered selections of 2 objects can be made from 6 distinct objects without replacement?
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Correct answer: D. 30
P(6,2) = 6!/(6−2)! = 30.
Question 26. How many ordered selections of 3 objects can be made from 7 distinct objects without replacement?
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Correct answer: C. 210
P(7,3) = 7!/(7−3)! = 210.
Question 27. How many ordered selections of 4 objects can be made from 8 distinct objects without replacement?
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Correct answer: B. 1680
P(8,4) = 8!/(8−4)! = 1680.
Question 28. How many ordered selections of 2 objects can be made from 9 distinct objects without replacement?
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Correct answer: A. 72
P(9,2) = 9!/(9−2)! = 72.
Question 29. How many ordered selections of 3 objects can be made from 10 distinct objects without replacement?
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Correct answer: D. 720
P(10,3) = 10!/(10−3)! = 720.
Question 30. How many ordered selections of 4 objects can be made from 11 distinct objects without replacement?
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Correct answer: C. 7920
P(11,4) = 11!/(11−4)! = 7920.
Question 31. How many ordered selections of 2 objects can be made from 12 distinct objects without replacement?
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Correct answer: B. 132
P(12,2) = 12!/(12−2)! = 132.
Question 32. How many ordered selections of 3 objects can be made from 13 distinct objects without replacement?
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Correct answer: A. 1716
P(13,3) = 13!/(13−3)! = 1716.
Question 33. How many 2-element subsets can be selected from 7 distinct elements?
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Correct answer: C. 21
C(7,2) = 7!/[2!(7−2)!] = 21.
Question 34. How many 3-element subsets can be selected from 8 distinct elements?
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Correct answer: B. 56
C(8,3) = 8!/[3!(8−3)!] = 56.
Question 35. How many 4-element subsets can be selected from 9 distinct elements?
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Correct answer: A. 126
C(9,4) = 9!/[4!(9−4)!] = 126.
Question 36. How many 2-element subsets can be selected from 10 distinct elements?
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Correct answer: D. 45
C(10,2) = 10!/[2!(10−2)!] = 45.
Question 37. How many 3-element subsets can be selected from 11 distinct elements?
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Correct answer: C. 165
C(11,3) = 11!/[3!(11−3)!] = 165.
Question 38. How many 4-element subsets can be selected from 12 distinct elements?
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Correct answer: B. 495
C(12,4) = 12!/[4!(12−4)!] = 495.
Question 39. How many 2-element subsets can be selected from 13 distinct elements?
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Correct answer: A. 78
C(13,2) = 13!/[2!(13−2)!] = 78.
Question 40. How many 3-element subsets can be selected from 14 distinct elements?
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Correct answer: D. 364
C(14,3) = 14!/[3!(14−3)!] = 364.
Question 41. How many length-2 sequences can be formed from 3 symbols if repetition is allowed?
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Correct answer: D. 9
Each of the 2 positions has 3 choices, giving 3^2=9.
Question 42. How many length-3 sequences can be formed from 4 symbols if repetition is allowed?
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Correct answer: C. 64
Each of the 3 positions has 4 choices, giving 4^3=64.
Question 43. How many length-4 sequences can be formed from 5 symbols if repetition is allowed?
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Correct answer: B. 625
Each of the 4 positions has 5 choices, giving 5^4=625.
Question 44. How many length-2 sequences can be formed from 6 symbols if repetition is allowed?
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Correct answer: A. 36
Each of the 2 positions has 6 choices, giving 6^2=36.
Question 45. How many length-3 sequences can be formed from 7 symbols if repetition is allowed?
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Correct answer: D. 343
Each of the 3 positions has 7 choices, giving 7^3=343.
Question 46. How many length-4 sequences can be formed from 8 symbols if repetition is allowed?
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Correct answer: C. 4096
Each of the 4 positions has 8 choices, giving 8^4=4096.
Question 47. How many length-2 sequences can be formed from 9 symbols if repetition is allowed?
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Correct answer: B. 81
Each of the 2 positions has 9 choices, giving 9^2=81.
Question 48. How many length-3 sequences can be formed from 10 symbols if repetition is allowed?
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Correct answer: A. 1000
Each of the 3 positions has 10 choices, giving 10^3=1000.
Question 49. If 4 objects are placed into 3 boxes, at least how many objects must share a box?
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Correct answer: C. 2
Since 4>3, some box contains at least two objects.
Question 50. If 5 objects are distributed among 2 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: B. 3
Ceiling(5/2) = 3, so some box has at least three objects.
Question 51. If 5 objects are placed into 4 boxes, at least how many objects must share a box?
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Correct answer: B. 2
Since 5>4, some box contains at least two objects.
Question 52. If 7 objects are distributed among 3 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: A. 3
Ceiling(7/3) = 3, so some box has at least three objects.
Question 53. If 6 objects are placed into 5 boxes, at least how many objects must share a box?
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Correct answer: A. 2
Since 6>5, some box contains at least two objects.
Question 54. If 9 objects are distributed among 4 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: D. 3
Ceiling(9/4) = 3, so some box has at least three objects.
Question 55. If 7 objects are placed into 6 boxes, at least how many objects must share a box?
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Correct answer: D. 2
Since 7>6, some box contains at least two objects.
Question 56. If 11 objects are distributed among 5 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: C. 3
Ceiling(11/5) = 3, so some box has at least three objects.
Question 57. If 8 objects are placed into 7 boxes, at least how many objects must share a box?
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Correct answer: C. 2
Since 8>7, some box contains at least two objects.
Question 58. If 13 objects are distributed among 6 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: B. 3
Ceiling(13/6) = 3, so some box has at least three objects.
Question 59. If 9 objects are placed into 8 boxes, at least how many objects must share a box?
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Correct answer: B. 2
Since 9>8, some box contains at least two objects.
Question 60. If 15 objects are distributed among 7 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: A. 3
Ceiling(15/7) = 3, so some box has at least three objects.
Question 61. If 10 objects are placed into 9 boxes, at least how many objects must share a box?
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Correct answer: A. 2
Since 10>9, some box contains at least two objects.
Question 62. If 17 objects are distributed among 8 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: D. 3
Ceiling(17/8) = 3, so some box has at least three objects.
Question 63. If 11 objects are placed into 10 boxes, at least how many objects must share a box?
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Correct answer: D. 2
Since 11>10, some box contains at least two objects.
Question 64. If 19 objects are distributed among 9 boxes, what minimum occupancy is guaranteed in some box?
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Correct answer: C. 3
Ceiling(19/9) = 3, so some box has at least three objects.
Question 65. How many edges are in the complete graph K4?
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Correct answer: A. 6
Every unordered pair of vertices forms an edge: 4(4−1)/2.
Question 66. How many edges does a simple cycle graph C4 have?
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Correct answer: D. 4
A cycle has one edge for each of its 4 vertices.
Question 67. How many edges are in the path graph P4 with 4 vertices?
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Correct answer: C. 3
A path through 4 vertices uses 4−1 edges.
Question 68. How many edges are in the complete graph K5?
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Correct answer: D. 10
Every unordered pair of vertices forms an edge: 5(5−1)/2.
Question 69. How many edges does a simple cycle graph C5 have?
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Correct answer: C. 5
A cycle has one edge for each of its 5 vertices.
Question 70. How many edges are in the path graph P5 with 5 vertices?
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Correct answer: B. 4
A path through 5 vertices uses 5−1 edges.
Question 71. How many edges are in the complete graph K6?
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Correct answer: C. 15
Every unordered pair of vertices forms an edge: 6(6−1)/2.
Question 72. How many edges does a simple cycle graph C6 have?
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Correct answer: B. 6
A cycle has one edge for each of its 6 vertices.
Question 73. How many edges are in the path graph P6 with 6 vertices?
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Correct answer: A. 5
A path through 6 vertices uses 6−1 edges.
Question 74. How many edges are in the complete graph K7?
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Correct answer: B. 21
Every unordered pair of vertices forms an edge: 7(7−1)/2.
Question 75. How many edges does a simple cycle graph C7 have?
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Correct answer: A. 7
A cycle has one edge for each of its 7 vertices.
Question 76. How many edges are in the path graph P7 with 7 vertices?
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Correct answer: D. 6
A path through 7 vertices uses 7−1 edges.
Question 77. How many edges are in the complete graph K8?
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Correct answer: A. 28
Every unordered pair of vertices forms an edge: 8(8−1)/2.
Question 78. How many edges does a simple cycle graph C8 have?
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Correct answer: D. 8
A cycle has one edge for each of its 8 vertices.
Question 79. How many edges are in the path graph P8 with 8 vertices?
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Correct answer: C. 7
A path through 8 vertices uses 8−1 edges.
Question 80. How many edges are in the complete graph K9?
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Correct answer: D. 36
Every unordered pair of vertices forms an edge: 9(9−1)/2.
Question 81. How many edges does a simple cycle graph C9 have?
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Correct answer: C. 9
A cycle has one edge for each of its 9 vertices.
Question 82. How many edges are in the path graph P9 with 9 vertices?
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Correct answer: B. 8
A path through 9 vertices uses 9−1 edges.
Question 83. How many edges are in the complete graph K10?
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Correct answer: C. 45
Every unordered pair of vertices forms an edge: 10(10−1)/2.
Question 84. How many edges does a simple cycle graph C10 have?
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Correct answer: B. 10
A cycle has one edge for each of its 10 vertices.
Question 85. How many edges are in the path graph P10 with 10 vertices?
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Correct answer: A. 9
A path through 10 vertices uses 10−1 edges.
Question 86. How many edges are in the complete graph K11?
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Correct answer: B. 55
Every unordered pair of vertices forms an edge: 11(11−1)/2.
Question 87. How many edges does a simple cycle graph C11 have?
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Correct answer: A. 11
A cycle has one edge for each of its 11 vertices.
Question 88. How many edges are in the path graph P11 with 11 vertices?
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Correct answer: D. 10
A path through 11 vertices uses 11−1 edges.
Question 89. A tree has 5 vertices. How many edges does it have?
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Correct answer: B. 4
Every finite tree has exactly |V|−1 edges.
Question 90. How many leaves does the star graph K₁,4 have?
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Correct answer: A. 4
All 4 outer vertices have degree one.
Question 91. A tree has 6 vertices. How many edges does it have?
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Correct answer: A. 5
Every finite tree has exactly |V|−1 edges.
Question 92. How many leaves does the star graph K₁,5 have?
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Correct answer: D. 5
All 5 outer vertices have degree one.
Question 93. A tree has 7 vertices. How many edges does it have?
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Correct answer: D. 6
Every finite tree has exactly |V|−1 edges.
Question 94. How many leaves does the star graph K₁,6 have?
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Correct answer: C. 6
All 6 outer vertices have degree one.
Question 95. A tree has 8 vertices. How many edges does it have?
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Correct answer: C. 7
Every finite tree has exactly |V|−1 edges.
Question 96. How many leaves does the star graph K₁,7 have?
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Correct answer: B. 7
All 7 outer vertices have degree one.
Question 97. A tree has 9 vertices. How many edges does it have?
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Correct answer: B. 8
Every finite tree has exactly |V|−1 edges.
Question 98. How many leaves does the star graph K₁,8 have?
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Correct answer: A. 8
All 8 outer vertices have degree one.
Question 99. A tree has 10 vertices. How many edges does it have?
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Correct answer: A. 9
Every finite tree has exactly |V|−1 edges.
Question 100. How many leaves does the star graph K₁,9 have?
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Correct answer: D. 9
All 9 outer vertices have degree one.
Question 101. A tree has 11 vertices. How many edges does it have?
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Correct answer: D. 10
Every finite tree has exactly |V|−1 edges.
Question 102. How many leaves does the star graph K₁,10 have?
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Correct answer: C. 10
All 10 outer vertices have degree one.
Question 103. A tree has 12 vertices. How many edges does it have?
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Correct answer: C. 11
Every finite tree has exactly |V|−1 edges.
Question 104. How many leaves does the star graph K₁,11 have?
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Correct answer: B. 11
All 11 outer vertices have degree one.
Question 105. In the complete graph K4, what is the degree of each vertex?
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Correct answer: D. 3
Each vertex is adjacent to the other 4−1 vertices.
Question 106. An undirected graph has 6 edges. What is the sum of all vertex degrees?
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Correct answer: C. 12
By the handshaking lemma, the sum of degrees is 2|E|=12.
Question 107. In the complete graph K5, what is the degree of each vertex?
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Correct answer: C. 4
Each vertex is adjacent to the other 5−1 vertices.
Question 108. An undirected graph has 7 edges. What is the sum of all vertex degrees?
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Correct answer: B. 14
By the handshaking lemma, the sum of degrees is 2|E|=14.
Question 109. In the complete graph K6, what is the degree of each vertex?
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Correct answer: B. 5
Each vertex is adjacent to the other 6−1 vertices.
Question 110. An undirected graph has 8 edges. What is the sum of all vertex degrees?
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Correct answer: A. 16
By the handshaking lemma, the sum of degrees is 2|E|=16.
Question 111. In the complete graph K7, what is the degree of each vertex?
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Correct answer: A. 6
Each vertex is adjacent to the other 7−1 vertices.
Question 112. An undirected graph has 9 edges. What is the sum of all vertex degrees?
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Correct answer: D. 18
By the handshaking lemma, the sum of degrees is 2|E|=18.
Question 113. In the complete graph K8, what is the degree of each vertex?
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Correct answer: D. 7
Each vertex is adjacent to the other 8−1 vertices.
Question 114. An undirected graph has 10 edges. What is the sum of all vertex degrees?
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Correct answer: C. 20
By the handshaking lemma, the sum of degrees is 2|E|=20.
Question 115. In the complete graph K9, what is the degree of each vertex?
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Correct answer: C. 8
Each vertex is adjacent to the other 9−1 vertices.
Question 116. An undirected graph has 11 edges. What is the sum of all vertex degrees?
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Correct answer: B. 22
By the handshaking lemma, the sum of degrees is 2|E|=22.
Question 117. In the complete graph K10, what is the degree of each vertex?
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Correct answer: B. 9
Each vertex is adjacent to the other 10−1 vertices.
Question 118. An undirected graph has 12 edges. What is the sum of all vertex degrees?
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Correct answer: A. 24
By the handshaking lemma, the sum of degrees is 2|E|=24.
Question 119. In the complete graph K11, what is the degree of each vertex?
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Correct answer: A. 10
Each vertex is adjacent to the other 11−1 vertices.
Question 120. An undirected graph has 13 edges. What is the sum of all vertex degrees?
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Correct answer: D. 26
By the handshaking lemma, the sum of degrees is 2|E|=26.
Question 121. A connected graph with exactly two odd-degree vertices (case 1) has which property?
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Correct answer: B. It has an Euler trail but no Euler circuit.
A connected graph has an Euler trail with different endpoints iff exactly two vertices have odd degree.
Question 122. A connected graph has all vertices of even degree. What Eulerian feature does it have?
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Correct answer: A. An Euler circuit
A connected graph with all even vertex degrees has an Euler circuit.
Question 123. How many odd-degree vertices may a finite undirected graph have?
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Correct answer: C. An even number
The handshaking lemma implies that the number of odd-degree vertices is even.
Question 124. Which graph has an Euler circuit?
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Correct answer: B. A cycle C5
Every vertex of the cycle C5 has degree 2 and the graph is connected.
Question 125. Does the path graph P5 have an Euler trail?
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Correct answer: A. Yes, but no Euler circuit
A nontrivial path has exactly two degree-one vertices and all other degrees equal 2.
Question 126. Can a connected graph with four odd-degree vertices have an Euler trail that uses each edge once?
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Correct answer: C. No
An Euler trail in a connected graph requires exactly zero or two odd-degree vertices.
Question 127. A simple cycle C6 has how many odd-degree vertices?
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Correct answer: D. 0
All six vertices have degree 2, so none has odd degree.
Question 128. For a connected graph with exactly two odd vertices u and v, where must an Euler trail start and end?
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Correct answer: B. At u and v in either order
In an open Euler trail the endpoints are exactly the odd-degree vertices.
Question 129. Which property must be identical in two isomorphic simple graphs (case 1)?
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Correct answer: A. Their sorted vertex-degree sequences
Graph isomorphisms preserve adjacency and thus every vertex degree.
Question 130. Two isomorphic simple graphs must have the same number of what?
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Correct answer: B. Vertices and edges
An isomorphism is a bijection on vertices that preserves adjacency and thus the edge count.
Question 131. If one simple graph contains a triangle and another has no triangles, can they be isomorphic?
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Correct answer: C. No
Graph isomorphisms preserve cycles of length three.
Question 132. Can two graphs with different numbers of connected components be isomorphic?
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Correct answer: A. No
An isomorphism preserves connectedness and the number of connected components.
Question 133. Which pair of graphs is isomorphic?
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Correct answer: D. Two copies of P5 with different vertex labels
Changing vertex labels does not alter the graph’s adjacency structure.
Question 134. Is having the same sorted degree sequence sufficient to guarantee that two simple graphs are isomorphic?
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Correct answer: B. No, not in general
Nonisomorphic graphs can have identical sorted degree sequences.
Question 135. If G is isomorphic to a tree T, which statement must hold?
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Correct answer: A. G is also a tree
Graph isomorphisms preserve connectedness and the absence of cycles.
Question 136. If two graphs are isomorphic, what happens to vertex adjacency?
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Correct answer: C. It is preserved under a bijection
The defining bijection of an isomorphism preserves adjacency.
Question 137. A weighted graph has edges A–B of weight 2, B–C of weight 3, and A–C of weight 8. What is the shortest A-to-C distance?
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Correct answer: D. 5
Compare the direct route (8) with A–B–C (2+3=5); choose the smaller.
Question 138. A weighted graph has edges A–B of weight 3, B–C of weight 4, and A–C of weight 9. What is the shortest A-to-C distance?
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Correct answer: C. 7
Compare the direct route (9) with A–B–C (3+4=7); choose the smaller.
Question 139. A weighted graph has edges A–B of weight 4, B–C of weight 5, and A–C of weight 10. What is the shortest A-to-C distance?
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Correct answer: B. 9
Compare the direct route (10) with A–B–C (4+5=9); choose the smaller.
Question 140. A weighted graph has edges A–B of weight 5, B–C of weight 6, and A–C of weight 11. What is the shortest A-to-C distance?
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Correct answer: A. 11
Compare the direct route (11) with A–B–C (5+6=11); choose the smaller.
Question 141. A weighted graph has edges A–B of weight 6, B–C of weight 7, and A–C of weight 12. What is the shortest A-to-C distance?
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Correct answer: D. 12
Compare the direct route (12) with A–B–C (6+7=13); choose the smaller.
Question 142. A weighted graph has edges A–B of weight 7, B–C of weight 8, and A–C of weight 13. What is the shortest A-to-C distance?
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Correct answer: C. 13
Compare the direct route (13) with A–B–C (7+8=15); choose the smaller.
Question 143. A weighted graph has edges A–B of weight 8, B–C of weight 9, and A–C of weight 14. What is the shortest A-to-C distance?
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Correct answer: B. 14
Compare the direct route (14) with A–B–C (8+9=17); choose the smaller.
Question 144. A weighted graph has edges A–B of weight 9, B–C of weight 10, and A–C of weight 15. What is the shortest A-to-C distance?
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Correct answer: A. 15
Compare the direct route (15) with A–B–C (9+10=19); choose the smaller.
Question 145. Find ⌊3.7⌋.
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Correct answer: C. 3
The floor is the greatest integer not exceeding 3.7.
Question 146. Find ⌈3.2⌉.
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Correct answer: B. 4
The ceiling is the least integer not less than 3.2.
Question 147. Find ⌊4.7⌋.
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Correct answer: B. 4
The floor is the greatest integer not exceeding 4.7.
Question 148. Find ⌈4.2⌉.
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Correct answer: A. 5
The ceiling is the least integer not less than 4.2.
Question 149. Find ⌊5.7⌋.
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Correct answer: A. 5
The floor is the greatest integer not exceeding 5.7.
Question 150. Find ⌈5.2⌉.
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Correct answer: D. 6
The ceiling is the least integer not less than 5.2.
Question 151. Find ⌊6.7⌋.
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Correct answer: D. 6
The floor is the greatest integer not exceeding 6.7.
Question 152. Find ⌈6.2⌉.
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Correct answer: C. 7
The ceiling is the least integer not less than 6.2.
Question 153. Find ⌊7.7⌋.
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Correct answer: C. 7
The floor is the greatest integer not exceeding 7.7.
Question 154. Find ⌈7.2⌉.
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Correct answer: B. 8
The ceiling is the least integer not less than 7.2.
Question 155. Find ⌊8.7⌋.
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Correct answer: B. 8
The floor is the greatest integer not exceeding 8.7.
Question 156. Find ⌈8.2⌉.
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Correct answer: A. 9
The ceiling is the least integer not less than 8.2.
Question 157. Find ⌊9.7⌋.
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Correct answer: A. 9
The floor is the greatest integer not exceeding 9.7.
Question 158. Find ⌈9.2⌉.
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Correct answer: D. 10
The ceiling is the least integer not less than 9.2.
Question 159. Find ⌊10.7⌋.
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Correct answer: D. 10
The floor is the greatest integer not exceeding 10.7.
Question 160. Find ⌈10.2⌉.
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Correct answer: C. 11
The ceiling is the least integer not less than 10.2.
Question 161. For f(n)=2n^2+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: A. Θ(n^2)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^2.
Question 162. For positive integers n→∞, which statement is correct? (2 is fixed)
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Correct answer: D. n^2 = o(n^3)
n^2/n^3=1/n→0, so the little-o statement holds.
Question 163. For f(n)=3n^3+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: D. Θ(n^3)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^3.
Question 164. For positive integers n→∞, which statement is correct? (3 is fixed)
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Correct answer: C. n^3 = o(n^4)
n^3/n^4=1/n→0, so the little-o statement holds.
Question 165. For f(n)=4n^4+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: C. Θ(n^4)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^4.
Question 166. For positive integers n→∞, which statement is correct? (4 is fixed)
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Correct answer: B. n^4 = o(n^5)
n^4/n^5=1/n→0, so the little-o statement holds.
Question 167. For f(n)=5n^5+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: B. Θ(n^5)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^5.
Question 168. For positive integers n→∞, which statement is correct? (5 is fixed)
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Correct answer: A. n^5 = o(n^6)
n^5/n^6=1/n→0, so the little-o statement holds.
Question 169. For f(n)=6n^6+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: A. Θ(n^6)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^6.
Question 170. For positive integers n→∞, which statement is correct? (6 is fixed)
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Correct answer: D. n^6 = o(n^7)
n^6/n^7=1/n→0, so the little-o statement holds.
Question 171. For f(n)=7n^7+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: D. Θ(n^7)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^7.
Question 172. For positive integers n→∞, which statement is correct? (7 is fixed)
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Correct answer: C. n^7 = o(n^8)
n^7/n^8=1/n→0, so the little-o statement holds.
Question 173. For f(n)=8n^8+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: C. Θ(n^8)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^8.
Question 174. For positive integers n→∞, which statement is correct? (8 is fixed)
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Correct answer: B. n^8 = o(n^9)
n^8/n^9=1/n→0, so the little-o statement holds.
Question 175. For f(n)=9n^9+5n+1, which is a tight asymptotic bound as n→∞?
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Correct answer: B. Θ(n^9)
A polynomial with positive leading coefficient grows at the rate of its highest power, n^9.
Question 176. For positive integers n→∞, which statement is correct? (9 is fixed)
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Correct answer: A. n^9 = o(n^10)
n^9/n^10=1/n→0, so the little-o statement holds.
Question 177. On the real numbers, classify f(x)=2x+1.
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Correct answer: C. Strictly increasing
The slope 2 is positive, so f increases strictly.
Question 178. On the real numbers, classify f(x)=3x+2.
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Correct answer: B. Strictly increasing
The slope 3 is positive, so f increases strictly.
Question 179. On the real numbers, classify f(x)=4x+3.
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Correct answer: A. Strictly increasing
The slope 4 is positive, so f increases strictly.
Question 180. On the real numbers, classify f(x)=5x+4.
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Correct answer: D. Strictly increasing
The slope 5 is positive, so f increases strictly.
Question 181. On the real numbers, classify f(x)=6x+5.
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Correct answer: C. Strictly increasing
The slope 6 is positive, so f increases strictly.
Question 182. On the real numbers, classify f(x)=7x+6.
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Correct answer: B. Strictly increasing
The slope 7 is positive, so f increases strictly.
Question 183. On the real numbers, classify f(x)=8x+7.
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Correct answer: A. Strictly increasing
The slope 8 is positive, so f increases strictly.
Question 184. On the real numbers, classify f(x)=9x+8.
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Correct answer: D. Strictly increasing
The slope 9 is positive, so f increases strictly.
Question 185. For f(x)=x², find f(2).
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Correct answer: B. 4
Squaring 2 gives 4.
Question 186. For f(x)=x², find f(3).
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Correct answer: A. 9
Squaring 3 gives 9.
Question 187. For f(x)=x², find f(4).
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Correct answer: D. 16
Squaring 4 gives 16.
Question 188. For f(x)=x², find f(5).
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Correct answer: C. 25
Squaring 5 gives 25.
Question 189. For f(x)=x², find f(6).
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Correct answer: B. 36
Squaring 6 gives 36.
Question 190. For f(x)=x², find f(7).
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Correct answer: A. 49
Squaring 7 gives 49.
Question 191. For f(x)=x², find f(8).
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Correct answer: D. 64
Squaring 8 gives 64.
Question 192. For f(x)=x², find f(9).
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Correct answer: C. 81
Squaring 9 gives 81.
Question 193. Which statement about a connected undirected graph with 4 vertices is correct?
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Correct answer: A. There is a path between every pair of vertices.
This path condition is exactly the definition of connectedness.
Question 194. A graph with exactly two connected components is what?
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Correct answer: B. Disconnected
A connected graph has exactly one connected component.
Question 195. In an undirected graph, if there is a path from u to v, what must also exist?
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Correct answer: A. A path from v to u
An undirected path can be traversed in reverse.
Question 196. How many connected components does a tree have?
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Correct answer: C. 1
A tree is connected by definition.
Question 197. Which graph is necessarily connected?
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Correct answer: D. The complete graph K6
Each pair of vertices of a complete graph is directly adjacent.
Question 198. Can a connected graph with 6 vertices have only 4 edges?
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Correct answer: B. No
Any connected graph with n vertices has at least n−1 edges, here 5.
Question 199. What is a bridge in a connected undirected graph?
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Correct answer: A. An edge whose removal disconnects the graph
A bridge is an edge whose deletion increases the number of connected components.
Question 200. What is a spanning tree of a connected graph with 8 vertices?
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Correct answer: C. A connected acyclic subgraph containing all 8 vertices
A spanning tree includes all vertices, is connected and acyclic, and has 7 edges.
